Question

A well insulated copper tank of mass 13 kg contains 4 kg of
liquidwater. Initially, the temperature of the copper is 27 °C
(300K) and the temperature of the water is 50 °C (323 K).
Anelectrical resistor of negligible mass transfers 100 kJ of
energyto the contents of the tank. The tank and its contents come
toequilibrium. What is the final temperature in °C?